Rotary spool for storage of convoluted photographic film or the like

ABSTRACT

A rotary spool for storage of convoluted elongated flexible strips (such as photographic film or magnetic tape) of the type having a relatively wide end portion followed by a relatively narrow neck portion has a substantially cylindrical core provided in its external surface with a circumferentially extending groove having a main section whose width slightly exceeds the width of a neck portion and a second section whose width slightly exceeds the width of an end portion. That part of the main section which is immediately adjacent to and communicates with the second groove section is flanked by a pair of ledges which overlie two internal recesses provided in the core and communicating with the part of the main section as well as with the second groove section at points located inwardly from the external surface of the core. When the end portion of a strip is inserted into the second groove section and is moved in a direction to enter the recesses of the core, the ledges hold the thus inserted end portion against separation from the spool. A projection in the part of the main groove section has a stop face which prevents the movement of end portion from the recesses back into the second groove section. The projection has a sloping surface located inwardly of the ledges and serving to guide the end portion from the second groove section into those ends of the recesses which are remote from the second groove section.

United States Patent [191 Blank et al.

[ ROTARY SPOOL FOR STORAGE OF CONVOLUTED PHOTOGRAPHIC FILM OR THE LIKE[75] Inventors: Rudolf Blank, ColognetAchim Kluczynski, Porz-Eil, bothof Germany [73] Assignee: Agta-Gevaert Aktiengesellschaft,

Leverkusen, Germany [22] Filed: July 31, 1972 [21] Appl. No.: 276,535

Primary Examiner.lohn W. Huckert Assistant ExaminerEdward J. McCarthyAttorney, Agent, or Firm-Michael S. Striker [11] 3,791,605 Feb. 12, 1974[57] ABSTRACT A rotary spool for storage of convoluted elongatedflexible strips (such as photographic film or magnetic tape) of the typehaving a relatively wide end portion followed by a relatively narrowneck portion has a substantially cylindrical core provided in itsexternal surface with a circumferentially extending groove having a mainsection whose width slightly exceeds the width of a neck portion and asecond section whose width slightly exceeds the width of an end portion.That part of the main section which is immediately adjacent to andcommunicates with the second groove section is flanked by a pair ofledges which overlie two internal recesses provided in the core andcommunicating with the part of the main section as well as with thesecond groove section at points located inwardly from the externalsurface of the core. When the 'end portion of a strip is inserted intothe second groove section and is moved in a direction to enter therecesses of the core, the ledges hold the thus inserted end portionagainst separation from the spool. A projection in the part of the maingroove section has a stop face which prevents the movement of endportion from the recesses back into the second groove section. Theprojection has a sloping surface located inwardly of the ledges andserving to guide the end portion from the second groove section intothose ends of the recesses which are remote from the second groovesection.

10 Claims, 3 Drawing Figures ROTARY SPOOL FOR STORAGE OF CONVOLUTEDPHOTOGRAPI'IIC FILM OR THE LIKE BACKGROUND OF THE INVENTION The presentinvention relates to improvements in spools or reels for storage ofconvoluted strip-shaped material, such as photographic roll film,magnetic tape or the like. More particularly, the invention relates toimprovements in spools or reels of the type wherein the core is providedwith means for separably or permanently retaining the specificallyconfigurated leader of a strip of photographic film or the like.

It is already known to provide the leader of a photographic film ormagnetic tape with a relatively wide end portion and a relatively narrowsecond or neck portion which is located immediately behind the endportion, i.e., between such end portion and the main portion of a filmor tape. It is also known to store such types of film or tape on spoolsor reels wherein the core is provided with a circumferentially extendinggroove having a width slightly or substantially less than the width ofthe neck protion and including a relatively wide section which canreceive the end portion of a strip. A portion of the groove is flankedby two ribs. Reference may be had to German Patent No. 1,101,947. Thedistance between the ribs is less than the width of the neck portion ofa strip. Consequently, when the relatively wide end portion of a stripis to be introduced into the wide section of such groove, the neckportion of the strip must be forced into the space between the ribswhich are provided with inclined faces to guide the neck portion intothe space therebetween. The end portion of the strip then abuts againstthe ribs and the neck portion is frictionally held between the ribs tothus prevent unintentional separation of the leader from the spool.

A drawback of the just described spool is that the at- I tachment of theleader of a film, tape or analogous strip material is a time-consumingoperation and also that the retention of the leader is not sufficientlyreliable. Another drawback of such spools is that the neck portion ofthe leader must undergo deformation in order to be properly receivedbetween and properly held by the ribs. Still further, the ribs do notprevent radially outward movement of the wide end portion of the leader.

SUMMARY OF THE INVENTION An object of the invention is to provide anovel and improved rotary spool or reel which is constructed andassembled in such a way that it allows for convenient attachment andinsures safe retention of the leader of a strip of photographic film,magnetic tape or the like.

Another object of the invention is to provide a spool or reel which isconstructed and configurated in such a way that the leader of a film orthe like need not be deformed prior to and/or during attachment to thecore.

A further object of the invention is to provide a spool or reel whichcan be used for storage of relatively long or short strips ofphotographic film, magnetic tape or the like, which can be constructedas a lightweight, one-piece body of metallic, synthetic plastic or othermaterial, and which can be utilized as a superior substitute forpresently known spools or reels which are employed as supply spools ortakeup spools in or independently of cassettes for photographic film ormagnetic tape in photographic cameras, projectors, tape recorders andlike apparatus.

Still another object ofthe invention is to provide a spool or reel whichallows for convenient attachment of the leader 'of a film or the likebut positively and invariably prevents accidental separation of theattached leader.

The invention resides in the provision of a rotary spool or reel forstorage of convoluted elongated flexible strips (e.g., photographicfilms or magnetic tapes) of the type having a leader including arelatively wide end portion and a relatively narrow second portionlocated behind the end portion and preferably having a length, asconsidered in the longitudinal direction of the strip, which exceeds thelength of the end portion. The spool comprises a core having apreferably cylindrical external surface provided with acircumferentially extending groove including an elongated main or firstsection of a width at least equal to that of the second portion of astrip but less than the width of the end portion of such strip and asecond section of a-width at least equal to that of the end portion of astrip. The

'municate with the aforementioned part of the first groove section aswell as with the second groove section. When the end portion of theleader of a strip .is inserted into the second groove section while thesecond portion of such strip extends outwardly from the aforementionedpart of the first groove section and the thus inserted end portion ofthe strip is moved in a direction toward the first groove section, theend portion is caused to enter into the recesses and is held by the ribsagainst separation from the core.

The novel features which are considered as characteristic of theinvention are set forth in particular in the appended claims. Theimproved spool itself, however, both as to its construction and its modeof operation, together with additional features and advantages thereof,will be best understood upon perusal of the following detaileddescription of certain specific embodiments with reference to theaccompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is an elevational view ofa spoolwhich embodies the invention;

FIG. 2 is a smaller-scale perspective sectional view of the spool, thesection being taken in the direction of arrows as seen from the lineII-Il of FIG. 1; and

FIG. 3 is a sectional view as seen in the direction of arrows from theline IIIIII of FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENTS length of the end portion b (asconsidered in the longi- I tudinal direction of the film 5) ispreferalby small, e.g., about one-third of its width. The length of theneck portion 5a is shown as being about twice its width and as beingapproximately equal to the width of the end portion Sb.

The illustrated spool further comprises two coupling portions 3 and 4which are respectively adjacent to the flanges I, 2 and serve toproperly mount and/or to drive the spool in a motion picture camera orprojector, not shown. In FIG. 2, the coupling portion 3 is attached to acomplementary coupling portion of a cinematographic apparatus 100. Theexact detailes of the coupling portions 3, 4 form no part of the presentinvention. It is be be noted that the spool may be provided with asingle flange, with two flanges l, 2 (as shown) or without any flange.

The surface 6A is provided with a circumferentially extending centrallylocated composite groove 7 including an elongated main section 7e havinga width slightly exceeding the width of the neck portion 5a and asection 7a whose width slightly exceeds the width of the end portion 5b.Still further, the core 6 is provided with two arcuate ribs or ledges 8,9 defining that part (7c) of the main groove section 7e which isimmediately adjacent to and communicates with the relatively widesection 7a. The part 7c is preferably of constant width. The ribs 8, 9overlie two recesses 7d which are provided in the core 6 so as tocommunicate at one end with the section 7a and also with the part 7c ofthe main groove section 7 e. The combined width of the two recesses 7dand part 7c (as considered in the axial direction of the core 6)preferably equals the width of the groove section 7a. Those ends(numbered 7b) of the recesses 7d which are remote from the section 7a asconsidered in the circumferential direction of the core 6, are boundedby axially and radially extending internal stop faces of the core 6. Theoverall length of the groove 7, as considered in the circumferentialdirection of the core 6, may be 360 (i.e., the groove 7 may be acircumferentially complete groove as shown in FIG. 2) or less. Thelength of the section 7a, as considered in the circumferential directionof the core 6, is preferably at least twice the length of the endportion 511 to thus allow for convenient introduction of the end portion5b into the section 7a, and the length of the recesses 7d preferablyexceeds the length of the end portion 5b and may but need not equal thatof the section 7a. As shown in FIG. 1, the length of the recesses 7d isabout three times the length of the end portion 5b. The distance betweenthe ribs 8, 9 (Le, the width of the part 70) may but need not euqal thewidth of the main groove section 7e. The external surfaces of the ribs8, 9 preferably form part of the cylindrical external surface 6A of thecore 6. The bottom surface of the core 6 in the groove 7 is shown at 10.

The core 6 is further provided with a separable, permanently attached orintegral projection 11 which extends outwardly from the bottom surface10 between the ribs 8, 9 and has at its left-hand end, as viewed in FIG.1, a radially extending stop face 11a spaced apart from the ends 7b ofthe recesses 7d by a distance which exceeds the length of the endportion 5b. The outer side of the projection 11 is a flat or convexsurface 11b which slopes gradually from the bottom surface 10 toward theoutermost portion of the stop face Ila and,

as shown in FIGS. 3, has its radially outermost part at 5 the generallevel of the internal surfaces of the ribs 8, 9. The width of theprojection 11 is preferably at least slightly less than the width of thepart 70 of the main groove section 7e. The leader of the film 5 isattached to the core 6 as follows: The manipulator insertes the endportion 5b into the groove section 7a, preferably to the right of theprojection 11, as viewed in FIG. 1, whereby the neck portion 5a extendsinto the part 7c of the main groove section 72. The manipulatorthereupon pulls the film 5 in a direction to the left (or rotates thecore 6 in a direction to the right, as viewed in FIG. Use that the endportion 5b slides along the sloping guide surface 11b of the projection11, under the ribs 8, 9 (i.e., into the recesses 7d) and ultimatelyassumes the position shown in FIG. 1 by phantom lines so that it islocated to the left of the stop face 11a. This completes the attachmentof the film 5 which is then prevented from being accidentally separatedfrom the core 6 because its end portion 5b is confined between the ends7b of the recesses 7d and the stop face 11a. To intentionally detach theleader of the film, the end portion 5b must be lifted radially outwardlyof the core 6 beyond the outermost portion of the stop face 11a andthereupon pushed in a direction to the right, as viewed in FIG. 1, so asto reenter the groove section 7a. Such movement of the end portion 5b isextremely unlikely or plain impossible in the course of normal use ofthe spool. When the end portion 5b assumes the position shown in FIG. 1,the neck portion 5a extends outwardly through the main section 7e of thegroove 7 and thus cannot interfere with the winding of the main filmportion 50 onto the external surface 6A of the core 6 between theflanges 1 and 2. Thus, the innermost convolution of the main filmportion 50 can lie flat against the surface 6A without any interferenceon the part of the neck portion 5a, ribs 8,9 and/or projection 11. Theattachment of the leader of film 5 to the core 6 requires little skilland can be completed very rapidly. Furthermore, the neck portion 5aand/or the end portion 5b need not undergo any deformation during and/orsubsequent to introduction of the end portion into the recesses 7d.

The projection 11 constitutes an optional but highly advantageousfeature of the improved spool. It prevents accidental withdrawal of theend portion 5b from the recesses 7d when the pull upon the film 5 (in adirection to the left, as viewed in FIG. 1) slackens or when the endportion 5b is pushed in a direction away from the ends 7b of therecesses 7d. The sloping guide surface 1 lb facilitates the introductionof the end portion 5b into the recesses 7d.

One of the recesses 7d can be omitted if the end portion 5b of theleader of the film 5 extends laterally only beyond one side of the neckportion 5a. In such instances, the groove section 7a can be modified sothat it extends only to one side of the main groove section 70. The justdescribed type of core can be used when the leader of the strip-shapedmaterial is rather stiff and can stand substantial tensional and bendingstresses.

It is further within the purview of the invention to provide the corewith two pairs of ribs 8, 9 and to place the groove section 7a betweenthe two pairs of ribs. Such a spool can be used for attachment of theleader ofa film or the like from the right-hand side or from theleft-hand side of the groove section 7a, as viewed in FIG. 1. The spoolthen preferably comprises two projections 11 one of which preventsremoval of the end portion 5b from the illustrated recesses 7d and theother of which prevents removal of the end portion 5b when the latter isreceived in the recesses which are located inwardly of the other pair ofribs.

The illustrated core 6 is integral with the projection 11 and consistsof synthetic plastic material.

Without further analysis, the foregoing will so fully reveal the gist ofthe present invention that others can, by applying current knowledge,readily adapt it for various applications without omitting featureswhich fairly constitute essential characteristics of the generic andspecific aspects of our contribution to the art and, therefore, suchadaptations should and are intended to be comprehended within themeaning and range of equivalence of the claims.

What is claimed as new and desired to be protected by Letters Patent isset forth in the appended claims:

1. A rotary spool for storage of convoluted flexible strips of the typehaving a leader including a relatively wide end portion and a relativelynarrow second portion behind the end portion, comprising a core havingan external surface provided with a circumferentially extending grooveincluding a first section of a width at least equal to that of thesecond portion of a strip and a second section of a width at least equalto that of the end portion of a strip, said core further having twospaced apart ribs flanking a part of said first section immediatelyadjacent to said second section and two recesses each overlapped by adifferent one of said ribs and each communicating with said secondsection as well as with said part of said first section whereby, whenthe end portion of a strip is inserted into said second section whilethe second portion of such strip extends outwardly through said part ofsaid first section and the thus inserted end portion is moved in adirection toward said first section, the end portion enters saidrecesses and is held by said ribs against separation from said core.

2. A spool as defined in claim 1, wherein said ribs have externalsurfaces forming part of said external surface of said core.

3. A spool as defined in claim 1, further comprising a projectionprovided in said part of said first section of said groove and having astop face extending substantially transversely of said ribs, thedistance between those ends of said recesses which are remote from saidsecond section, as considered in the circumferential direction of saidcore, being at least equal to the length of the end portion of a stripas considered in the longitudinal direction of such strip.

4. A spool as defined in claim 3, wherein said core has a second surfaceconstituting the bottom surface of said groove, said projectionextending outwardly from said second surface and having a guide surfacesloping outwardly from said second surface toward said stop face toguide the end portion of a strip from said second section toward andinto said ends of said recesses whereby the end portion is held by saidstop face against movement back toward said second section.

5. A spool as defined in claim 4, wherein said guide surface is a flatsurface.

6. A spool as defined in claim 4, wherein said guide surface is a convexsurface.

7. A spool as defined in claim 1, wherein the length of said secondsection of said groove and said recesses, as considered in thecircumferential direction of said core, exceeds the length of the endportion of the leader of a strip as considered in the longitudinaldirection of such strip.

8. A spool as defined in claim 1 further comprising at least one flangeadjacent to one axial end of andextending radially beyond said core.

9. A spool as defined in claim 1, wherein said ribs have internalsurfaces outwardly adjacent to the respective recesses and furthercomprising a projection provided in said groove in the region of saidsecond section and said part of said first'section and extendingoutwardly substantially to the level of said internal surfaces, saidprojection having a stop face extending substantially transversely ofsaid ribs and substantially radially of said core, said recesses havingends remote from said second section and the distance between said endsof said recesses and said stop face being at least equal to the lengthof the end portion of a strip, as considered in the longitudinaldirection of such strip.

10. A spool as defined in claim 9, wherein said projection is integralwith said core and said core consists of synthetic plastic material.

1. A rotary spool for storage of convoluted flexible strips of the typehaving a leader including a relatively wide end portion and a relativelynarrow second portion behind the end portion, comprising a core havingan external surface provided with a circumferentially extending grooveincluding a first section of a width at least equal to that of thesecond portion of a strip and a second section of a width at least equalto that of the end portion of a strip, said core further having twospaced apart ribs flanking a part of said first section immediatelyadjacent to said second section and two recesses each overlapped by adifferent one of said ribs and each communicating with said secondsection as well as with said part of said first section whereby, whenthe end portion of a strip is inserted into said second section whilethe second portion of such strip extends outwardly through said part ofsaid first section and the thus inserted end portion is moved in adirection toward said first section, the end portion enters saidrecesses and is held by said ribs against separation from said core. 2.A spool as defined in claim 1, wherein said ribs have external surfacesforming part of said external surface of said core.
 3. A spool asdefined in claim 1, further comprising a projection provided in saidpart of said first section of said groove and having a stop faceextending substantially transversely of said ribs, the distance betweenthose ends of said recesses which are remote from said second section,as considered in the circumferential direction of said core, being atleast equal to the length of the end portion of a strip as considered inthe longitudinal direction of such strip.
 4. A spool as defined in claim3, wherein said core has a second surface constituting the bottomsurface of said groove, said projection extending outwardly from saidsecond surface and having a guide surface sloping outwardly from saidsecond surface toward said stop face to guide the end portion of a stripfrom said second section toward and into said ends of said recesseswhereby the end portion is held by said stop face against movement backtoward said second section.
 5. A spool as defined in claim 4, whereinsaid guide surface is a flat surface.
 6. A spool as defined in claim 4,wherein said guide surface is a convex surface.
 7. A spool as defined inclaim 1, wherein the length of said second section of said groove andsaid recesses, as considered in the circumferential direction of saidcore, exceeds the length of the end portion of the leader of a strip asconsidered in the longitudinal direction of such strip.
 8. A spool asdefined in claim 1 further comprising at least one flange Adjacent toone axial end of and extending radially beyond said core.
 9. A spool asdefined in claim 1, wherein said ribs have internal surfaces outwardlyadjacent to the respective recesses and further comprising a projectionprovided in said groove in the region of said second section and saidpart of said first section and extending outwardly substantially to thelevel of said internal surfaces, said projection having a stop faceextending substantially transversely of said ribs and substantiallyradially of said core, said recesses having ends remote from said secondsection and the distance between said ends of said recesses and saidstop face being at least equal to the length of the end portion of astrip, as considered in the longitudinal direction of such strip.
 10. Aspool as defined in claim 9, wherein said projection is integral withsaid core and said core consists of synthetic plastic material.